Water may be used as a storage medium for heat. In residential and commercial settings, this may be accomplished by use of a water storage tank. The tank is filled with water and then heat energy from an external source, such as solar collectors, geothermal heating, biomass, wood pellets, cogeneration, or even traditional fossil fuels or electrical sources, is used to raise the temperature of the water in the tank. The heat energy stored in the water may then be extracted for use in space heating or for domestic hot water purposes, or the heated water itself may be used for these purposes. Because water is capable of absorbing and retaining a great amount of heat energy, it is a cost-effect medium for storing heat energy that is collected or generated at a time other than when it is to be used.
Typically, water storage tanks are constructed of steel and are lined with glass or concrete or some other massive material which insulates and helps retain heat. The tanks are also often wrapped in bulky insulation. However, this method of tank construction creates heavy and cumbersome tanks that are difficult to install. For example, the basement of a home or building is often the desired location for a water storage tank, but access to a basement is usually through a narrow staircase or small window. Therefore, traditional water storage tanks were usually limited in size, reducing the amount of heat energy that could be stored and eliminating efficiencies. In order to use make use of larger quantities of water to store heat energy (say, over 100 gallons), either multiple small tanks were necessary or large tanks were built on site, at substantial cost.
There have been attempts to solve the problem of bringing large tanks into difficult to access locations. For example, U.S. Pat. No. 4,660,594 (Apr. 28, 1987), to Gocze, discloses a portable collapsible tank for storing and insulating heated water, in which the tank is comprised of an elongate flexible and foldable outer cylindrical sleeve formed with sufficient tensile strength to support the tank and water stored therein. These tanks could store up to 1500 gallons and were relatively easy to install, though time consuming. However, the water storage tanks of the '594 patent are not structurally rigid, thereby leading to some inherent disadvantages, primarily that they are not designed to bear a load on their covers. Thus, persons climbing onto or placing objects on top of these tanks could inadvertently cause failure. Moreover, the substantially circular footprint of these tanks is an inefficient use of floor space.
There thus remains a need for a water storage tank that is easy to manufacture, ship, and store, while providing the capability of storing a large quantity of water for long term retention of heat energy for later uses, which is also quick and easy to assemble in any location, is significantly stronger than previously patented tank designs, has a more efficient square configuration to better fit into buildings, and is structurally rigid to provide a greater margin of safety during use.
It is therefore an object of an aspect of the invention to provide an improved modular insulated water tank which is easy to manufacture, ship, and store.
It is a further object of an aspect of the invention to provide an improved modular insulated water tank which is easy to assemble and disassemble for use in difficult to access locations.
It is yet a further object of an aspect of the invention to provide an improved modular insulated water tank capable of storing a large quantity of water for long term retention of heat energy for later uses.
It is yet a further object of an aspect of the invention to provide an improved modular insulated water tank that is structurally rigid and capable of bearing external weight without failure.
It is yet a further object of an aspect of the invention to provide an improved modular insulated water tank that utilizes an efficient footprint to better fit within a structure.
It is yet a further object of an aspect of the invention to provide an improved modular insulated water tank which may be easily integrated with an external heating source, such as a boiler, solar collectors, a wood stove, a geothermal heating system, a biomass heating system, cogeneration, a fossil fuel burner, or electrical heat source.
It is yet a further object of an aspect of the invention to provide an improved modular insulated water tank which efficiently integrates with a space heating system or a domestic hot water system.
It is yet a further object of an aspect of the invention to provide an improved modular insulated water tank which can be easily reconfigured to contain greater or lesser quantities of water for heat energy storage purposes, as needed.
Other objects of this invention will be apparent to those skilled in the art from the description and claims which follow.